Opaleye wrapped up in classy MTL attire. https://github.com/benkolera/opaleye-classy/tree/master

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MIT licensed by Ben Kolera
Maintained by ben.kolera@gmail.com


Classy MTL extension of the lovely Opaleye library, which simply just wraps things up in a MonadReader , MonadError context where the config/error are constrained by Classy Lenses/Prisms rather than by concrete non-extensible types.

More info on this pattern can be found in George Wilson's BFPG talk:



  • This will only work if you only talk to one DB in your transformer stack.
  • This API is missing a few IO operations from [[http://hackage.haskell.org/package/opaleye-]].If you need other functions exported then let me know or drop in a PR.
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